Salivary biomarkers for clinical applications

For clinical applications such as monitoring health status, disease onset and progression, and treatment outcome, there are three necessary prerequisites: (i) a simple method for collecting biologic samples, ideally noninvasively; (ii) specific biomarkers associated with health or disease; and (iii) a technology platform to rapidly utilize the biomarkers. Saliva, often regarded as the 'mirror of the body', is a perfect surrogate medium to be applied for clinical diagnostics. Saliva is readily accessible via a totally noninvasive method. Salivary biomarkers, whether produced by healthy individuals or by individuals affected by specific diseases, are sentinel molecules that could be used to scrutinize health and disease surveillance. The visionary investment by the US National Institute of Dental and Craniofacial Research, the discovery of salivary biomarkers, and the ongoing development of salivary diagnostic technologies have addressed its diagnostic value for clinical applications. The availability of more sophisticated analytic techniques gives optimism that saliva can eventually be placed as a biomedium for clinical diagnostics. This review presents current salivary biomarker research and technology developmental efforts for clinical applications.